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Know the West

Super mouse to the rescue


What's three inches long and can leap tall buildings in a single bound?

It's a bird. It's a really, really small plane. No! It's the Preble's meadow jumping mouse!

Well, maybe it can't leap over a building, but the little rodent can jump a foot and a half up in the air, cover twice that distance horizontally, and swivel its 6-inch-long whip of a tail to change direction mid-flight. Its most supernatural feat, however, is not vaulting over buildings, but stopping them from being built in the first place.

The mouse, which is listed as threatened under the Endangered Species Act, has achieved the seemingly impossible: protecting some areas from sprawl on Colorado's ever-urbanizing Front Range.

Environmentalists have long considered the PMJM -- as the mouse is coolly labeled in scientific papers (an acronym that brings to mind a mouse wearing pajamas) -- the ticket to conserving riparian areas threatened by those relentless housing developments that march along the eastern flanks of the Rockies. Efforts to shield creek and stream banks from suburban construction got an extra boost on December 14 when the U.S. Fish and Wildlife Service announced an expansion of critical habitat for the mouse in Colorado. Federal agencies have to consult with the Service on actions they carry out, authorize, fund, or permit, that may affect critical habitat, and the Service tells them how to avoid harming the mice. Now, 110- to 140-meter wide strips of critical habitat are designated along each side of 411 miles of streams and rivers in the Front Range, an addition of 177 new miles to previously designated habitat.

Conservation groups including the Center for Native Ecosystems and Save the Poudre are celebrating the decision, which corrects notorious Interior staffer Julie MacDonald's manipulation of scientific data that stripped some areas of protection in the early 2000s. Meanwhile, they continue litigation in hopes of restoring Endangered Species Act protection for the mouse in Wyoming. In 2008, the Wyoming populations of Preble's mice were removed from the threatened species list.

An economic analysis [pdf] predicts that the new critical habitat designation may cost landowners, developers, builders and others somewhere between $28.2 and $84.9 million to modify development plans, mitigate or enhance habitat to protect the shrubby riparian areas where the mouse lives, and delay building while they acquire permits over the next 20 years. Residential and commercial development on private land would bear the brunt of the cost, especially between Denver and Colorado Springs, assuming the housing market recovers from its current stagnancy. The designation could affect an estimated 4,540 new housing units in 88 large-scale and 65 small-scale developments over the next two decades. Road and bridge construction, water development, and other activities may also accrue expenses to protect mouse habitat.

But, the economic analysis points out, there are also economic benefits to conserving land for endangered species including enhanced habitat for other wildlife, improved water quality, and increased property values adjacent to the conserved open space plus "improved environmental quality, which in turn may have collateral human health or recreational use benefits." Even Superman would be proud to achieve so much.

Emilene Ostlind is a High Country News editorial intern.

Super-mouse illustration by Shaun Gibson.